How to Hang an Interior Door

Adding another room to your house will be complete once you install an interior door. The least time consuming interior door to install is a pre-hung door. Pre-hung doors come in a wide variety of sizes and designs, so you are sure to find one that complements your home's décor. Once you have a door selected, you can install it yourself in a few hours.

Step 1

Measure the rough opening for the interior door with a tape measure. You want to purchase a pre-hung door that is 2 inches narrower than the rough opening. A 36-inch opening will require a 34-inch pre-hung door. This will accommodate the extra for the door jamb for the interior door. Purchase a pre-hung interior door at a big box hardware store or a door dealer. Purchase a thin piece of plywood the same length as the door frame and at least 2-foot long and some shims.

Step 2

Place the pre-hung door on a set of saw horses. The door is pre-assembled to the door frame. The door jambs will be longer than you need and will have to be cut. Measure each door jamb from the top of the opening to the floor. Transfer the measurement to the appropriate door jamb for each side.

Step 3

Cut each door jamb to your measurements with a circular saw. Set the pre-hung door and frame into the opening with assistance from a helper. Use a 4-foot level to check the hinge side jamb for plumb. Insert shims where necessary between the door jamb and the rough opening. Check the hinge side jamb again with the level. Drive a nail halfway into the bottom, middle and top of the hinge side jamb after the jamb is plumb. You are just tacking the door jamb at this point.

Step 4

Set the level on the header of the door frame, and check the square of the header. Raise up on the opposite jamb until the door header is level. Check the plumb of the opposite door jamb with the level and shim where necessary. Tack the door jamb with nails at the bottom, middle and top of the jamb.

Step 5

Drill pilot holes for wood lags on the hinge side jamb. Place two holes near the bottom, two holes near the top and two more sets of holes between the top and bottom. Use a Phillips-head screwdriver drill attachment to drive 3-inch wood screws into the pilot hole and jamb to secure the hinge side jamb to the rough opening.

Step 6

Recheck the level of the door header with the level. Nail the opposite door jamb to the wall using 8d finishing nails. Secure the header to the door opening with 8d finishing nails. Attach the door opening trim on both sides of the door opening with 4d finishing nails.